1 files changed, 38 insertions, 0 deletions
diff --git a/platform/javascript/emscripten_helpers.py b/platform/javascript/emscripten_helpers.py
new file mode 100644
index 0000000000..a55c9d3f48
--- /dev/null
+++ b/platform/javascript/emscripten_helpers.py
@@ -0,0 +1,38 @@
+import os
+
+
+def parse_config():
+    em_config_file = os.getenv("EM_CONFIG") or os.path.expanduser("~/.emscripten")
+    if not os.path.exists(em_config_file):
+        raise RuntimeError("Emscripten configuration file '%s' does not exist" % em_config_file)
+
+    normalized = {}
+    em_config = {}
+    with open(em_config_file) as f:
+        try:
+            # Emscripten configuration file is a Python file with simple assignments.
+            exec(f.read(), em_config)
+        except StandardError as e:
+            raise RuntimeError("Emscripten configuration file '%s' is invalid:\n%s" % (em_config_file, e))
+    normalized["EMCC_ROOT"] = em_config.get("EMSCRIPTEN_ROOT")
+    normalized["NODE_JS"] = em_config.get("NODE_JS")
+    normalized["CLOSURE_BIN"] = os.path.join(normalized["EMCC_ROOT"], "node_modules", ".bin", "google-closure-compiler")
+    return normalized
+
+
+def run_closure_compiler(target, source, env, for_signature):
+    cfg = parse_config()
+    cmd = [cfg["NODE_JS"], cfg["CLOSURE_BIN"]]
+    cmd.extend(["--compilation_level", "ADVANCED_OPTIMIZATIONS"])
+    for f in env["JSEXTERNS"]:
+        cmd.extend(["--externs", f.get_abspath()])
+    for f in source:
+        cmd.extend(["--js", f.get_abspath()])
+    cmd.extend(["--js_output_file", target[0].get_abspath()])
+    return " ".join(cmd)
+
+
+def create_engine_file(env, target, source, externs):
+    if env["use_closure_compiler"]:
+        return env.BuildJS(target, source, JSEXTERNS=externs)
+    return env.Textfile(target, [env.File(s) for s in source])